German exports and imports dropped much more than expected in May, data showed today, coming after other soft indicators that have signalled Europe's largest economy is losing momentum. 

Exports - the traditional backbone of Germany's economy - struggled last year and fell in three of the first five months this year.

This weighed on overall German growth and made the economy reliant on imports. 

Figures from the Federal Statistics Office showed seasonally-adjusted exports fell by 1.1% on the month, while imports dropped 3.4%, the steepest monthly fall since November 2012. 

The trade surplus widened to a seasonally adjusted €18.8 billion from a revised €17.2 billion in April and compared with a Reuters consensus forecast for €16.4 billion. 

Today's figures follows signs from other data - such as a slump in industrial output, weak orders and retail sales - that Europe's growth locomotive is in for a weaker second quarter than expected. 

While some economists are beginning to cut their second-quarter expectations after a strong first quarter, Unicredit also pointed to other factors that weighed on exports in May. 

"On the one hand the export drop is a reaction to the strong rise in the previous month," the bank said, referring to an increase of 2.6% in April. "On the other hand, the long weekend after the May 1 holiday is likely to have weighed on exports," it added. 

The drop in imports, however, was more worrying as it may signal emerging weakness in the domestic economy. 

Domestic demand and a strong labour market drove the German economy to 0.8% growth in the first three months of the year, its fastest rate in three years. The government forecasts growth of 1.8% for the year as a whole. 

Economists polled by Reuters had expected exports to fall by 0.3% and imports to increase by 0.5%.